I've been fixing up a Vespa Bravo that belonged to a friend of mine. It's got a Malossi 65cc kit on it with a Proma Circuit pipe. It's been one damn thing after another with this bike. I finally got it up and running, then the aluminum head gasket blew. I fixed that, and it seemed to be running great again, but after hitting 40 or so on a long flat, the engine halted completely and while the back wheel didn't lock up, the clutch immediately acted as a hard brake.
Taking off the cylinder, looks like I soft-seized. The culprit seems to have been a leak around the paper gasket on the cylinder base, though it wasn't ripped. It did run after I let it cool down, without any obvious problems. My question is this, though--judging from the scuffing on the piston and cylinder, is there anything I can do to clean that stuff up (and if so, generally what does it cost)? Secondarily, the bottom piston ring broke (I believe this is a result of me trying to get the cylinder back on, not the soft seize)--can I run with just the top one, or is that like, super dumb or whatever?
Thanks for any help and/or advice.